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Space EnvironmentHow do objects in space travel? |
Space is huge, and even our immediate environment is gigantic. We are the third planet from the Sun, and the third of three inner planets, all of which are right next to the Sun compared to others. The picture below shows the planets in their orbits on the orbital plane. You have to look carefully to see our home. The four inner planets (Mercury, Venus, Earth and Mars) are in the tiny disk in the center, inside of Jupiter's orbit.
Image from The Nine Planets, a Multimedia tour of the Solar System by Bill
Arnett http://seds.lpl.arizona.edu/nineplanets/nineplanets/nineplanets.html
The planets are far from the Sun, travel huge distances in space, and take a long time to do so. Pluto takes almost 250 years to go around the Sun completely and travels almost 5 billion miles to do so!
| OBJECT |
Distance from Sun (average) |
Distance traveled in one complete orbit of the Sun (one "year.") | Amount of time for one complete orbit of the Sun (one "year.") |
| Sun | 0 miles | ||
| Mercury | 36,800,000 miles | 57,900,000 miles | 3 Earth months |
| Venus | 65,100,000 miles | 108,200,000 miles | 7 Earth months |
| Earth | 93,000,000 miles | 149,600,000 miles | 1 Earth year (365.25 days) |
| Mars | 139,500,000 miles | 227,900,000 miles | 23 Earth months. Almost 2 Earth years. |
| Jupiter | 483,600,000 miles | 778,300,000 miles | 142 Earth months. Almost 12 Earth years. |
| Saturn | 883,500,000 miles | 1,427,000,000 miles | 354 Earth months. (29.5 Earth years) |
| Uranus | 1,785,600,000 miles | 2,869,600,000 miles | 1008 Earth months. (84 Earth years) |
| Neptune | 2,790,000,000 miles | 4,496,600,000 miles | 1978 Earth months (almost 165 Earth years) |
| Pluto | 3,627,000,000 miles | 4,913,500,000 miles | 2976 Earth months (248 Earth years) |
The distance from the Sun is average because the orbits of the planets do not make perfect circles, but rather very slightly flattened ones, or ellipses.
What causes an orbit to happen?
How do spacecraft use an orbit to move from planet to planet?
